There's more revealed in the leak. There are two new colors shown off. There's a lovely-looking lilac, and a very fetching orange. They also appear smaller in the hand than the older Powerbeats Pro ...

Either way, one of the most accurate ways to track your heart rate during intense exercise is to use a chest strap heart rate monitor ... giving you a clearer picture of how it's performing.

such as chest strap heart rate monitors or electrocardiograms. However, if you're looking for an easy way to get a potential measurement of your heart rate, there are smartphone apps out there ...